Computer systems utilize backup to create duplicate copies of programs, disks or data for archiving purposes or to safeguard valuable files from loss should an active copy be damaged or destroyed. FIG. 1 illustrates a conventional tape backup system 100 having a server 110, an application program 130, a communications channel 150 and tape storage 170. The server 110 runs the application program 130 which manages tape storage 170. Tape storage 170 may be one or more tape drive devices or one or more tape library devices. The data channel 150 provides bi-directional communication for transferring commands and data between the application program 130 and tape storage 170. In particular, backup data is written from the server 110 to tape storage 170, and restore data is read from tape storage 170 to the server 110. Also, commands are sent from the server 110 to tape storage 170 and status data is sent from tape storage 170 to the server 110 in response. For example, an inquiry command may yield a tape device model and serial number in response, a mode sense command may yield a block size value in response, and a log command may yield error data in response.